try a few nights without the orange juice and then try it again. if you do find a connection then just don't give oj at night. for most people this would not be an issue but it may be for you and your child.
can drinking orange juice at night cause upset stomach in the morning? . my child has been waking with an upset stomach in the morning that lasts a few hours. she's been drinking natural orange juice with pulp at night. not sure if there is a connection. sometimes when i drink the oj late at night my stomach is a little crazy in the morning.