Not a dinosaur, or any other species of animalia. But scientists have taken prehistoric seeds and grew them, using in vitro technology, to adult plants. The seeds were from before the last ice age, around 31,800 years ago. The plants grew to maturity, and need to be cross-fertilized to reproduce.
This is the new most ancient, multicellular, viable, living organism. The previous record-holder was from a 2000 year old seed from Masada.
This reminds me of Norway’s Seed Vault in Svalbard.