It's not that they don't approve. In fact, they both like their in-laws. Bonnie's still a bit cautious around Nick but that's instinctive. Lillian, as I call her, is actually very fond of Judy. Neither of them understand why Nick and Judy are so hesitant on the thought of having kids. They just bring it up much gentler with Judy than with him. This is how they bring up the subject with Nick, especially when they're both present.