Novak Djokovic and wife Jelena's touching post for son on his birthday

Novak Djokovic with wife Jelena and son Stefan

Serbian tennis star Novak Djokovic's son Stefan turned four recently and Djokovic and his wife Jelena took to social media to wish him.

Djokovic tweeted this throwback picture and wrote: "You have been a blessing to all since you arrived. I am so grateful to have you as my son, my brave falcon and knight You shine light & love on our souls. Thank you for teaching us how to be present, enjoy & smile, forgive & move on. Happy bday my dear son Love you."

Meanwhile, Jelena tweeted: "Welcome to Kissington! We only spread love, kisses and hugs around here. No wonder kids grow so fast in our town! Happy birthday my little boy #4yearsold."

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