May 12 (UPI) -- Aquaman and The Stand actress Amber Heard announced on Instagram Sunday that she has welcomed twins into her family.

Amber Heard is swimming into a new chapter of parenthood, just in time for Mother's Day. The Aquaman alum surprised fans on Sunday by announcing that she is officially outnumbered by her children — Heard was already mother to 4-year-old Oonagh and has now welcomed a set of twins.

"Aquaman" star Amber Heard reflected on "becoming a mother by myself and on my own terms" in a Mother's Day post revealing she has welcomed twins.