Actor Tyler Posey is in mourning after his mother lost her battle with breast cancer.

Cyndi Terese Garcia-Posey passed away earlier this month (12Dec14), aged 55, after fighting the disease for more than four years.

Speculation about her death spread in early December (14), when the Teen Wolf star announced he was taking a break from social media, and reports were confirmed on Sunday (28Dec14), when her obituary was posted in the local newspaper in Santa Clarita, California, where she resided.

The actor broke his silence on Twitter.com on Saturday (27Dec14) to share his gratitude for the outpouring of support from his followers, writing, "Just want to say thank you for all the love and the support my guys. you all mean so much to me. I wish I could repay the favor!"

Posey recently paid tribute to his mum on Zoe Saldana's new Aol webseries, My Hero, in which celebrities honour those who have been huge influences in their lives.

In the episode, the actor gushed over his mum's perseverance, saying, "My mum is a hero to me - I don't think I could pull off her bravery... She kept our family together while going through chemo (therapy) and dying... She's been this rock. She knows how much we love her, and she deserves to hear it."

Posey surprised his emotional mum with a gift basket of Irish goods and a trip for her and her husband to go on a dream vacation in Ireland.

Cyndi, who served as a business and guidance manager for her son throughout his career, is survived by her other two boys, Derek and Jesse, and her husband John.