I am glad you like Lark! Have you named her now?
If not, with the Xmas Day update, I want to offer up
Aurora Dominique -
"Dominique is a name of French origin, meaning "of the Lord." It is a form of the masculine name Dominic, derived from the Latin name Dominicus meaning "belonging to the Lord." Dominique is a beautiful biblical name making it an excellent choice for baby born on Sunday, "the Lord's day.""
I knew a Dominic who was born on Xmas Day, I was told then it meant Day of the Lord (I've always been a name nerd!), but looking it up to clarify, the name sites are saying it's just 'of the lord' - nice if you have any xtian leanings.
If not, I couldn't help myself from picking something super special for an Xmas Day baby - I LOVE Lark, but I'd go for a festive name or something beginning with X.
Aurora Elvie
Aurora Holly
Aurora ...
Amaryllis is a beautiful flower associated with Christmas. This Greek moniker, meaning 'to sparkle' was first used as an appellation of pastoral beauties.
Angelina, the subtle variation of Angel and Angela, sounds festive without sounding over the top.
I love the AA alliteration!
Gloria is a jubilant Christmas-inspired name, coming from the Latin word for "glory,"
Others here:
https://nameberry.com/list/412/christmas-baby-names
Or go with Lark, and I will forever feel thrilled I helped name another human!