Credit: Troian Bellisario's Instagram Photo: Troian Bellisario From Season 1

The stars of Pretty Little Liars have really grown up since the series premiered in 2010, and thanks to Keegan Allen's (Toby) recent Instagram photo, we're taking a walk down Memory Lane.

Keegan posted a flashback photo of his on-screen girlfriend, Troian Bellisario (Spencer), writing, "season one spencer. @sleepinthegardn with my bellow camera." Oh, yesteryear, how we miss you! Troian’s response? “What a baby I was!” A pretty little baby, Tro!

Aside from just looking a bit more mature in Season 4, Troian has also accomplished a lot since the start of Pretty Little Liars. Along with starring on the hit ABC Family show, she also landed the lead role in the short film, Exiles. What's more, our girl Troian also played Lauren in the webseries of the same name.

We're so proud of this Hastings lady! How much do you love Troian? Weigh in below.

Catch the next episode of Pretty Little Liars on Tuesday, June 18, 2013 at 8 p.m. ET/PT on ABC Family.