Not sure how far I will take this. The first chapter will be sort of like a starting point for if anyone else wants to do a story like this. This will take place after Bruce dies of natural causes, which means he's staying dead. Here is who each of the Bat Family is at this point in their lives:

Dick Grayson/Batman II(39 years old)- adopted first son of Bruce Wayne, currently training Terry.

Barbara Gordon/Oracle(37 years old)- daughter of Police Commissioner James Gordon,provides support to both Bat Family and Birds of Prey.

Jason Todd/Red Hood(32 years old)- adopted second son of Bruce Wayne, killing criminals in the slums of Gotham, will go after high ranking villains for the right price.

Tim Drake-Wayne/ Red Robin(25 years old)- adopted third son of Bruce Wayne, keeping an eye on Jason and helping Dick when he can.

Cassandra Cain/ Black Bat(24 years old)- adopted daughter of Bruce Wayne, currently out of communication with Batcave.

Stephanie Brown/ Batgirl(23 years old)- taken in by Batman, though not officially adopted by Bruce Wayne, considering going back to her original costumed identity, Spoiler.

Damian Wayne/ Robin(approx. 17 years old/never comments on his age)- first biological son of Bruce Wayne, working, begrudgingly, with Batgirl while Dick trains Terry.

Martha Wayne(14 years old)- biological daughter of Bruce Wayne, a secret child between Bruce and Diana(to make the Batman X Wonder Woman fans happy) who was trained to be the new Batgirl, or even go further by becoming Wonder-Bat, to honor both of her parents.

Terrance "Terry" Wayne(10 years old)- second biological son/possible clone of Bruce Wayne, the only person truly destined to become the new Batman, currently being trained by Dick.

...

Dick was working on the Bat Computer, going through old files in case one of the more obscure villains from his days as Robin, or even before then, decided to make a comeback. He was about to close the folder he was searching when something caught his eye behind the "X" icon. He closed the folder so he could read the title of the new folder.

"Project Tomorrow," Dick read aloud before opening it.

In it were schematics for things Dick probably would have said would be cool when he was a kid. A flying Batmobile, a strength augmenting Batsuit, jet boots, all things that he would have seen in a Saturday morning cartoon and asked Bruce if he would be able to build. He then saw Bruce's note.

All of the schematics are finished and ready to be sent to Lucius. However, I know I will never be able to use these myself given my advancing age. Therefore, I have devised a way for Gotham to receive a Batman worthy of these items. My only regrets are that none of my disciples, my children, will ever be ready to use these and that I may never see the day that they are used. So I leave the responsibility of enacting Project Tomorrow to you Dick. You are the only person who can take up my mantle and finish what I have started. There is a freezer hidden underneath my first suit. It will only open when you type in the pass-code "Beyond". Take what is inside to Selina, she'll know what to do. Wait ten years before you return to her, she'll have him ready by then. It's up to you now Dick.

I know you won't let me down, Bruce.

Dick sat there for a few moments. He reread the note a few times to make sure he didn't hallucinate the words. He then deleted the note and sent the schematics to Lucius Fox. Afterwards, he got up and made his way to the hall of suits and stopped before Bruce's oldest suit, the original Batsuit. He knelt down and felt the base of the pedestal. There was a gap between the base and the floor. He carefully pushed the pedestal to reveal the freezer. It had a keypad on it. Dick carefully punched in the letters. B-E-Y-O-N-D. There was a beep, then a click and the freezer hissed open. Inside was a black canister. dick carefully removed it and didn't dare open it. He made his way to the Batmobile and place the canister securely in the glove compartment. He then got in the driver's seat and hit the ignition.

It didn't take long for Dick to arrive at Selina Kyle's apartment. He pulled the canister out of the glove compartment and pulled a slip of paper and a pen out after. He folded the paper in half and wrote Selina's name on the top flap. Then, on the inside, he wrote, Bruce said you'd know what to do.

Dick pulled the cowl on before exiting the Batmobile. He shot a grapple line that took him up to Selina's floor. He saw her through the bedroom window and placed the canister in the flower bed outside her window, note up, and knocked on the glass before dropping down. He saw her window open as he climbed back into the Batmobile. With her looks, she could have been half Bruce's drove off as soon as he saw her pick up the canister. Now all he could do was wait.

...

11 years later

Damian sighed as he heard a knock on the door. He had gotten used to fending for himself in the Manor back when his father was Batman, however, he couldn't shake the empty feeling the house seemed to have without Alfred. He descended the stairs quickly as the knocking sounded a second time. Damian opened the door to see a woman and a girl waiting outside. They both had long black hair and blue eyes.

"Well, you've certainly grown since the last time I saw you, Damian," The woman commented.

It was Diana Prince, more commonly referred to by this family as Wonder Woman, former Princess, now Queen of the Amazons and the current God of War.

"Five years will do that," Damian commented turning to the girl, something about her features seemed familiar, "and who's this?"

"Ma...a W..ne," the girl muttered.

"What was that?" Damian asked.

"There's no need to be shy with him," Diana patted the girl's back, which seemed to push the word out.

"Martha Wayne," she hurriedly placed her hands over her mouth as though she had unintentionally swore.

"What?" Damian gave her the look he normally reserved for criminals that are hiding information from him.

"She's your half-sister," Diana explained, "Bruce and I had more than our fair share of private sessions when he was alive. I figured it was time for her to meet her father's side of the family."

"Great," Damian sighed, "a brother last year and a sister now. Is this family ever going to wait at least a generation before expanding again?" Damian turned and proceeded into the manor. He stopped and turned back, "Are you coming or not?"

The women followed Damian through the manor and down into the Batcave. As they descended the steps, they could hear the sounds of combat. when the cave itself came into view, a young boy was hurled back across the cave and would have hit the Bat Computer if he hadn't grabbed the chair. The chair slid as far as it could before the boy jumped off and used the wall behind the Bat Computer to propel himself forward, towards Dick, who caught him and threw him in the other direction. The boy caught a hold of the wall, but a split second too late, as it only changed his trajectory and caused him to crash in the hall of suits. The group hurried down in time to see Dick pull a mannequin wearing Barbara Gordon's second Batgirl suit off of the boy.

Dick spotted the group and acknowledged Damian first.

"Finally going to train with your brother?" He asked.

"He'd have a better chance with the mannequin," Damian said before ascending the steps back to the manor.

"Diana," Dick nodded to the queen before turning to Martha, "you must be Martha. Themyscira's little Bat."

Martha cautiously stepped forward, eyeing Dick.

"I'm Dick Grayson. Your dad adopted me before he had any kids. I'm holding on to the Batman name until your little brother Terry here," Dick put his arm on the boy's shoulder, "is ready for it." He shoved Terry forward, "Go on Terry, say hi to your sister."

When neither one said anything, Dick turned to Diana.

"How old is she?" He asked.

"Fourteen." She replied, "And him?"

"Ten. I have five years minimum to get him ready."

"Well, if the Batgirl title is free, Martha is more than ready for it." Diana stated.

"You'll have to take that up with Stephanie," Dick explained, then realized something, "Did you already know that your daughter is named after Bruce's mom?"

"Of course, that's why I chose the name."

"Right," Dick turned to Martha, "So, do you think you'd like to try sparring with your little brother? Just to see where each of you are."

Martha looked at Dick, then Terry, and immediately took off her civilian clothes, revealing that she had already prepared her own Batgirl costume. It had dark red armor with a gold bat on her chest and an indigo unsersuit, the colors of Wonder Woman. She opened a pouch on her belt and shocked everyone but Diana when she pulled out a cape and cowl. She put the cowl on and the cape flowed down. She put her hands on her hips and looked at her brothers.

"Not bad," Dick commented, "But Terry's is better. He's not old enough for it yet, but it's still better."

Martha scoffed and walked off, no longer in the mood to fight. Diana looked at Dick, who merely shrugged, before following her daughter.

...

So, there's the start. I'm not sure if I'll finish it, but if continue from here on, be my guest. I just wanted to start on a more original thought for how Terry could fit into the more convoluted, yet completely canon, Bat Family.