Tyson tries his best to avoid celebrating his birthday, but there are forces working against him.
Jethro.
Jethro is actively working against him and frequently ambushes Tyson on his birthday to force his younger brother to have fun for once. Something that Tyson isn’t as grateful to him for as Jethro thinks he should be, in that Tyson is not at all grateful.
One of Jethro’s more successful attempts at forcing Tyson to enjoy his birthday was making his babysit for James on a day that happened to be his birthday, and if he happened to do nice things for his brother it was ‘definitely absolutely as thanks for babysitting and absolutely no other reason’.
Before that, the best birthday Tyson can remember is back in his army days with Sebastian. His birthday happened to co-inside with the time between deployments, and Tyson found himself tangled in hotel room sheets with Sebastian, lazily working their way through room service strawberry cake and overly sweetened hot chocolate whilst watching re-runs of Blue Planet.