Janet Jackson enjoyed a low-key 50th birthday this week. The 'Together Again' hitmaker reached the milestone age on May 16 and marked the day with her family and a few close friends as she is determined to stay healthy and not "overdo it" while pregnant with her and husband Wissam Al Mana's first child. A source said: "Her support system is extremely strong. Janet received many calls from her loved ones that couldn't be there with her on her birthday. "She is taking things easy these days and is feeling well but not overdoing it in any capacity of her life. Janet is staying healthy for her and her baby." The 'When I Think of You' hitmaker "can't wait" to have her baby. The source told E! News: "She's been praying for a child for a very long time. She's already in the process of thinking of baby names." And the insider revealed her late brother Michael Jackson's name "may be part" of what she calls her child in tribute to the King of Pop, who died of acute Propofol intoxication in June 2009. Janet's brother Jermaine recently admitted he thinks his sister will be a great mother. He said: "She'll be a great mother because she is very tough, very strict. "But I tell her, 'If you need any parenting skills or baby skills, let me know because I'm the best diaper changer there is on this planet, still to this day.'..." But the pregnancy news has been a shock to Jermaine because he still thinks of his little sister as "a baby". He said: "My sister Janet is my baby. She is fine but she's having a baby. A baby having a baby. We look at her like our little baby and now she's grown and having a baby. I'm proud to be an uncle and I can't wait to see how this baby is going to look."