It took Sam longer than he liked to admit to realize that Tony was hiding something.
Since he came back from Afghanistan, and after the mess with Obadiah, it wasn't unusual for Tony to keep his shirt on when they went to bed or had sex. Sam knew it wasn't easy for Tony, and he wasn't about to force him to do something Tony wasn't yet comfortable with.
The first time after he got the Arc reactor and Sam had tried to take off his shirt had nearly sent him into a panic attack and Sam was more than understanding about Tony's limits.
But he still should have noticed sooner; especially since it wasn't the only hint that something was wrong.
Tony was behaving erratic, more so than he ever did before Afghanistan, he was pale and clammy, and then Tony tried to cook for him. That should have been a clear warning sign for Sam, but he somehow hadn't seen it.
So when Rhodey called him, it hit him unprepared.
"What's up with Tony?" Rhodey asked without any pleasantries and Sam frowned.
"What do you mean?"
"You did notice his behaviour, didn't you?" Rhodey said incredulously, as if there was any chance that Sam had missed Tony's stunt in Monaco.
"I did," Sam pressed out. "But I don't know."
"Well, you better figure it out, because he is burning through Arc cores like it's nothing and there is some strange discolouration on his neck. He wouldn't tell me, but I hope you have more luck, being his husband and all," Rhodey told him and then promptly hung up.
Sam stared at the phone for a few seconds before he went to find Tony. Maybe it's time to push some boundaries.
Sam found Tony slumped over some plans for his birthday and just the size of it gave Sam pause. Tony used to party like this before Afghanistan, but even then it never happened in his own home. Sam had been suspicious before so even if Rhodey hadn't called, this would be a dead giveaway that something was wrong.
Tony didn't notice him, too caught up in his plans and too busy drinking the horrible green concoction, and Sam took the time to really study him.
He seemed dead tired, and there was an unhealthy sheen to his face, not to mention the bags under his eyes. And since Rhodey had pointed it out, Sam also paid special attention to his neck. There really were some strange black markings crawling up his neck and Sam's stomach dropped with worry.
"Tony, what is going on?" Sam asked without preamble and Tony flinched at his words.
Sam couldn't tell if it was because he hadn't noticed, or if it were the words itself that startled Tony.
"Nothing, angel, just stressed with my party planning," Tony cheekily said after he gathered himself, but Sam didn't let him do this today.
"Then don't plan a party," Sam told him and now Tony turned around.
"It's for my birthday," Tony explained like Sam didn't know that.
"You didn't need a party last year. Or the year before. What's changed now?"
Tony squirmed, like Sam had him pinned down, and Sam felt bad for doing this, but it was clear as day that Tony was hiding something and Sam wasn't about to let this go on.
"Fine, if you don't want to answer that, why don't you tell me what's that on your neck?"
Tony's hand flew up to his neck and he avoided Sam's gaze. Sam crouched down next to him and gently removed Tony's hand from his neck.
"What's going on, love?" he gently asked and Tony dropped his head.
"Nothing," he mumbled and Sam barely suppressed a sigh.
"You wanna try that again, with maybe a bit more truth?"
Sam could pinpoint the exact moment Tony shut down.
"It's nothing you need to worry about," Tony sharply told him. "I'm gonna figure it out, like I always do."
"I don't doubt that," Sam reassured him. "But if you told me what was going on, I could maybe help."
Tony scoffed at that. "Help, sure. No offense, honey, but you are not smart enough to help me."
Sam knew exactly what Tony was doing, they weren't just married since yesterday, but it still stung, and Sam did nothing to hide that hurt. It usually was the best way to show Tony that he had gone too far, and it helped today as well.
"I'm sorry. You know what I mean. I'm sorry," Tony quickly said and rubbed his eyes. "I'm just tired."
"I can see that," Sam told him. "And I could help, you know. Even if it was just with cooking you dinner and being there for you. But for that I have to know what's going on."
Sam could tell that Tony wasn't about to tell him what was wrong and Sam seriously questioned why Tony didn't trust him with this.
"Alright, then don't tell me," he quietly said and kissed Tony's knuckles. "But know that I am here for you, no matter what."
Tony didn't meet his eyes but he nodded and briefly smiled at him when Sam pressed another kiss to his temple.
Sam stood in the kitchen for a few minutes, unconsciously clenching his hands, before he took a deep breath and started with his dinner preparations. Tony didn't come out when he called for him, so Sam dropped a plate by his workshop, without saying a word, but when he came by later to tell Tony that he was heading to bed, he found the plate empty. At least Tony was still eating.
Sam wasn't a stranger to an empty bed, Tony used to stay up all night before Afghanistan and even after, but this night felt different and Sam had a hard time falling asleep.
He was barely dozing when he felt the mattress dip next to him and he immediately reached out for Tony who burrowed into his chest.
Sam wanted to ask, again and again, but Tony was shaking in his arms as it was and so Sam stayed quiet.
"It's the reactor," Tony eventually whispered into Sam's skin and Sam squeezed him to let him know that he was listening.
"The core, it's palladium," Tony went on and then faltered.
Sam felt him swallow a few times and Sam soothingly stroke his back.
"Is that where the marks come from? It's the core?" Sam cautiously asked and Tony nodded.
"It's poisoning me," he finally admitted and Sam's heart stopped.
"You're dying. Again," Sam pressed out, voice thick with tears.
"I'm gonna figure it out," Tony promised and kissed his neck. "I'm gonna figure it out."
"You don't sound too sure," Sam whispered and buried his face in Tony's hair.
"I will, I just have to figure out with what to replace it."
"So the thing keeping you alive is killing you," Sam summed this whole mess up and almost laughed with the irony of it.
They lay in silence for a few minutes before Sam said "That's the reason for the big party." It hit Sam like a bucket of cold water. "You think it will be your last."
Tony pushed himself up on an arm, looking down at Sam and a small, sad smile on his face.
"I don't know. It could be. I don't know," he said and Sam could see the fear in his eyes.
"You're gonna figure it out," Sam repeated his own words back to Tony. "And I'm gonna be here for you, no matter what. And I know you can do it."
"At least you have faith in me," Tony joked and Sam rose up to kiss him.
"Always," he promised and then dragged Tony down with him. "Let's sleep now, so you can be a genius tomorrow and save your life."
Tony chuckled, but quickly quieted down and pressed closer.
"I hope you're right," he mumbled.
"I always am, you know that," Sam replied and slung an arm around Tony. "And besides, you're not about to leave me for a reason as stupid as this."
"That's true," Tony agreed and then quickly fell asleep.
Sam didn't even try to sleep as well, instead he opted to watch over Tony this night. He hoped he would get to do it for a long time, but for now he would take whatever he could get.