Troian Bellisario has led tributes to Shay Mitchell after she gave birth to her first child.

The 'Pretty Little Liars' star posted a sweet message for her friend and co-star as she announced she had welcomed her first child with her boyfriend Matte Babel.

Troian wrote in the comment section on Instagram, alongside a heart eyes emoji: ''Most beautiful babe and mother.''

Whilst co-star Keegan Allen shared: ''So happy for you and your beautiful family!''

Vanessa Hudgens wrote: ''Omg babe. Congratulations.''

Shay announced she had given birth to her first child on Instagram, captioning the post: ''Never letting go... (sic)''

The 32-year-old actress recently opened up about having anxiety about sharing her pregnancy news, after having previously suffered a miscarriage.

She said: ''I previously had a miscarriage and that experience gave me anxiety about sharing the news of this pregnancy with anyone outside of our parents. With the first pregnancy, I was elated and told everyone at eight weeks. However, I wanted to be sure that this second pregnancy would be viable before shouting it from the rooftops, so I hid it for nearly six months and became very antisocial.

''Usually, I'm incredibly active and outgoing, but instead, I mainly stayed home to avoid stares and questions. I was extremely lonely.''

During the time she kept her pregnancy a secret, the 'Mother's Day' star was ''paranoid'' that people would think she was gaining weight when her body began to change, and as a result, she began to suffer from pre-partum depression.

She explained: ''As long as I can remember, I've heard about postpartum depression. However, to be depressed at the beginning came as a shock. The isolation and anxiety I experienced was crippling. I thought I was going out of my mind and questioned why nobody ever talked to me about this phase. I've been fortunate since sharing the news of my pregnancy to have some amazing conversations with other pregnant women and moms and know that all these feelings are 'normal,' so now we just need to normalise them by discussing more openly!''