I recommend buying another one. My grandchildren had a Fischer price thing that made music, had moving fish, and played soothing songs. I don't think we changed the batteries more than once in 2-3 years. I wonder if your stars one was faulty. Does the star turn its self off after a certain period? If not perhaps your husband could rig that up. Also some batteries last longer than others. They cost a bit more but last a lot longer. We used Duracell Coppertop (alkaline) ones.
To save money you could use rechargeable batteries. You can buy the charger with the batteries. I think it cost less than $15 and my daughter uses these batteries for several things.
I'm for anything that helps a toddler go back to sleep. He will out grow it. I've gone thru times in my life that I turned on the radio to help me get back to sleep. Songs and a mesmerizing display are soothing in part because the moving objects sort of "hypnotize" the watcher, making them sleepy. Many people have a fish tank that they use to help themselves unwind and get sleepy. We all use aides to sleep from time to time. This is the time for this toddler.
My daughter came to live with me when she was 7. A friend's daughter gave her a gloworm. She took it back to Waverly and slept with it during the get acquainted time. She continued sleeping with it for a couple of months. I think it gave her security. First, it represented her new home and then was a constant object for her when she did move to my house.
For those who haven't seen a glowworm, they have a light that turns on when you squeeze it.