Produce a 3-minute Swahili song in the key of D major with an upbeat Angusha beat, incorporating a fusion of Kenyan coastal rhythms and Afro-pop elements. The song should exude a joyful and romantic mood, celebrating the motherly love of Justina Ngina from Makueni, now residing in Sabaki Athi River, towards her children Jason, Jaelyn, and Janaya. The track should feature an introduction, two verses, a catchy and repeatable chorus, a dynamic bridge, and a smooth outro. Utilize percussion instruments, marimba, and guitar to create a lively and engaging sound. Maintain a moderate tempo ranging between 100-110 BPM to keep the energy high throughout the song.