Katherine McNamara Calls Luke Baines 'Plus One for Life' in Sweet Birthday Post

Katherine McNamara has the sweetest birthday wishes for Luke Baines!

The Thundermans actress took to Instagram on Saturday (June 8) to share her sentiments with her Shadowhunters co-star as he turned 29 years old.

“Happy birthday to my brother dearest and partner in crime – a truly incredible human @lukebaines,” she captioned the slideshow.

“From weddings, to festivals, to karaoke nights in – you never cease to make me smile,” she added. “You wear your heart on your sleeve and give so much of yourself to those you love. All my love! #plusoneforlife.”

Love it! In April, Luke Baines confirmed that he and Katherine McNamara still aren’t dating.