Myrtle Burrows
From Tolkien Gateway
Myrtle Burrows was the third child and only daughter of Milo Burrows and Peony Baggins. As her mother was a Baggins, Myrtle was related to both Bilbo Baggins and Frodo, but only in a most distant way (through her great-great-great-grandfather Balbo Baggins, in fact). We only know for sure about one event from her life: she attended Bilbo's famous one hundred and eleventh Birthday Party. At that time, she would have been just eight years old.