An analysis of a tiny tyrannosaurid jaw bone and claw have been used to extrapolate probable egg and baby size.
https://www.sciencedaily.com/releases/2021/01/210125113121.htm
https://www.bbc.com/news/uk-scotland-edinburgh-east-fife-55796799
The paywalled article published in the Canadian Journal of Earth Sciences. I'd be interested in the methodology if I can find a free source complete article.
https://cdnsciencepub.com/doi/abs/10.1139/cjes-2020-0169