Angela Cartwright and Veronica Cartwright through the years: From 'Sound of Music' to 'Alien' to today

Few child actors ever got to experience Hollywood quite like Veronica Cartwright and Angela Cartwright.

The English-born sisters grew up in Los Angeles, where they were welcomed into the Hollywood circuit at very young ages. Veronica's earliest roles were in episodes of "Leave it to Beaver" and "The Twilight Zone," and she was just barely a teen when she was cast in Hitchcock's "The Birds."

Meanwhile, younger sister Angela was acting professionally as well, landing her first role at just three years old. She spent an impressive seven seasons on the air in "The Danny Thomas Show" before snagging a spot as one of the Von Trapp children in "The Sound of Music."

See Angela Cartwright through the years:

As she hit her teenage years, Angela continued working steadily. She most famously played Penny Robinson on "Lost In Space." But after tying the knot in 1976, she mostly refocused her attention on her two children and her photography. She's now 66.

Veronica, for her part, continued to rack up more roles, appearing in countless TV shows and movies through the years. Seriously, her resume never ends! From '90s shows like "Baywatch" and "ER" to more recent shows like "7th Heaven" and "Revenge," Veronica, now 69, is truly a Hollywood staple.

See Veronica Cartwright through the years: