Olivia Wilde and Jason Sudeikis' little boy is almost too cute for words!

The 32-year-old actress took to Instagram on Monday, March 28 to share an adorable new photo of her 23-month-old son, Otis, at the dentist — and we can't get over grown up he looks in the pic!

"Better behaved than I've ever been at the dentist. Guess they gave him the good drugs," Olivia captioned the sweet snapshot of her son happily showing off his teeth during the doctors visit.

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Olivia and her fiancé, Jason, 40 — who first started dating in 2011 and became engaged in January 2013 — welcomed Otis, their only child, in April 2014.

Click through the gallery below to see more of Hollywood’s cutest kids!