Janet Jackson can't wait to celebrate her first Mother's Day!
A source close to the 50-year-old singer's family tells ET that she'll be spending Sunday with her brother, Randy Jackson, and her son, Eissa, who was born in January.
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"This baby is everything to her and she is ecstatic about being a mother," the source said. "It's changed the focus of her life and showed her how even more precious human life is. Janet believes her son is truly a blessing from above."
And once the celebrations are over, Jackson, who shares Eissa with estranged husband Wissam Al Mana, will get right back into her fitness routine. The pop star is currently gearing up for her State of the World Tour (previously titled Unbreakable), which kicks off Sept. 7 in Lafayette, Louisiana.
"Janet is juicing right now and doing the super cleanse next. She is eating a little bit, but just lean proteins and vegetables," the source explained. "This regime will put her back in fighting shape for her tour. She is also going to be working with a trainer to get back in tip-top form."
An additional source previously told ET earlier this month that Jackson is preparing for this to be "her greatest tour ever."
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"She'll be coming out full force and unrestricted," the source added. "Janet will begin rigorously dieting. She wants to look her best for herself and her fans."
More on that in the video below!