Lindsay Lohan has treated her Twitter followers to a glimpse of her as a smiley-faced tot.

Long before she became famous for her hard-partying and bad break-ups, the Mean Girls star was a chubby-cheeked cutie.

The actress - who got her first taste of fame as a child model at the age of three - posted the black-and-white baby photos along with the caption, "guess who. Hahahahahaha."

Her followers on the microblogging site were quick to praise her for being a cute baby.

So, what happened?

More celebrity baby photos