Did he overstep his authority ?

When my cousin was married to her first husband, she had a baby girl . She later divorced her first husband . When she was married to her second husband, she had a baby boy . She later divorced her second husband . At one point, she married her third husband . At this point, the girl was a teenager, and the boy was a few years younger . Her third husband told her children they weren't allowed to date . I think my cousin should have told him "Don't make rules for MY kids !", and the kids should have told him to stick it . I've had a few people tell me he overstepped his authority . I know he was trying to prevent a bunch of deadbeats from jumping the girl and getting her pregnant, but I think he was overdoing it . NOW -- did he overstep his authority ? Does a stepparent have a right to lay down a "No Dating" rule ? Thank you in advance for your answers .