Millie Bobby Brown's boyfriend Jacob Sartorius has posted a glowing tribute to the star for her birthday.

Millie Bobby Brown and Jacob Sartorius via Instagram (c)

Millie Bobby Brown and Jacob Sartorius via Instagram (c)

The 'Stranger Things' actress turned 14 on Monday (19.02.18) and her 15-year-old boyfriend was quick to take to social media as soon as midnight hit to ring in her special day with a heartfelt post on Instagram.

Posting a snap of the pair together, the 'Chapstick' singer wrote: "Happy birthday to this beautiful girl, 14!! you're the funniest, most caring person in the entire world. I hope this year brings you lots of great memories and moments you remember forever. Can't wait to see you, I love you and miss you so much!! Everybody go wish this girl a happy birthday @milliebobbybrown (sic)"

Millie and Jacob confirmed their romance at the end of last year when they were spotted celebrating New Year's Eve (31.12.17) with her family at Walt Disney World in Florida.

Dating rumours had been circling the pair since October when Millie posted a photo with the singer-songwriter on her Instagram story, and they have since exchanged comments on social media.

Fans noticed that the actress liked one of Jacob's tweets which read "just another day w you on my mind (sic)" on January 8, and four days later Millie posted a picture on her Instagram account of herself cuddling a teddy bear.

She wrote "Thanks for the bear" with a red heart emoji and he replied "[Of] course" with a matching emoji.

Meanwhile, the young star recently revealed she has become close friends with rapper Drake, whom she credits with helping "guide" her through fame.

She said: "We met in Australia and he asked me to go to his show ... and it was probably the best performance I've ever seen! It's Drake and he's great ... I have great people around me to help guide me through this, and he's one of those people."