Change wasn't just happening in Westeros but also in the life of Nyra and her family. Their Lord, Uhtred, was finally able to retake his ancestral seat and finally be the Lord of Bebbanburg as his father had wanted, long ago. This meant that Nyra, Sihtric and their family relocated from their home in Mercia to Bebbanburg to follow their Lord.
Sihtric, and later their eldest two sons, fought for Uhtred for another decade before, several years after the passing of King Edward, and during the reign of the first King of the English, King Aethelstan, Lord Uhtred was wounded in battle and perished several days later. He was 79 years old. During his tenure as Lord of Bebbanburg, Uhtred had seen first Mercia, East Anglia and then Northumbria and York fall under control of King Alfred's son and then grandson.
Uhtred was succeeded by his son Uhtred.
As for Nyra and her family, in total she would birth 16 children in her life, all of whom would live to adulthood. By the time Uhtred died, she and Sihtric would already have a half dozen grandchildren of their own. She did in fact, learn of her father's plot to abduct her and force her back to Westeros where he, her own sire, planned to fuck a baby into her belly. It seriously appalled and disgusted her to learn that he wanted to sire his own grandchild.
When she got the message from him requesting that she send some of her daughters back to Westeros to marry her aging sire, both she and Sihtric nearly vomited at the thought. King Viserys was nearing 70 years of age making him 48 years older than their firstborn daughter and 51 than their second which were the only two of marriageable age. Luckily, both girls were also happily married with the eldest having already successfully birthed three babes and the second being pregnant with her first. Their other daughters were aged 10, 8, 6 and 3 and thus too young to even consider being wedded or bedded.
For reference here is when each child was born and their respective ages compared to their mother.
Rhaenyra birthed Young Sihtric at age 17.
Rhaenyra birthed Roderick at age 19.
The eldest daughter was born when she was 21.
The second daughter is born when she's 24.
The twin boys are born when she's 26.
The fifth son is born when she's 29.
Her first set of triplets (2 boys and a girl) are born when she's 30.
Her forth daughter is born when she's 32.
She has twin girls at 34.
Her second set of triplets (2 girls and a boy) are born when she's 37.
At aged 40 her children are 23, 21, 19, 16, 14, 11, 10, 8, 6 & 3 and the eldest 4 children are married.