Jenna Bush Hager and her family are all in big celebration mode as they marked a huge family milestone.MORE: What Jenna Bush Hager has said about her rebellious teenage yearsThe Today Show host announced that over the weekend, she celebrated her niece's very first birthday.The Bush family got together to wish Cora Georgia Coyne, Jenna's twin sister Barbara Bush's daughter with husband Craig Coyne, a very happy first birthday. It is her first child with her husband, who she married in 2018.WATCH: Jenna Bush Hager explains why the Queen's death was a surprise to King Charles IIIMORE: Jenna Bush Hager wears figure-hugging dress and strappy heels for late night television appearanceDetailing all of the celebrations, the mother-of-three spoke to co-host Hoda Kotb about her birthday party, sharing an adorable selfie with Barbara and baby Cora, who has a crown on her head."There was some celebrating going on at your house," Hoda said, and both immediately gushed over how fast she was growing up and how adorable she looked in her little birthday crown.Jenna gave a glimpse of what the family got up to, saying: "So we had breakfast tacos, and some queso...