Whilst Rigsby is on holiday in Spain, Alan lets a room to Mrs. Brent, whose husband is at sea, and her baby, despite the fact that Rigsby does not allow tenants with children. So, whilst Mrs. Brent looks for other accommodation, Alan tries to hide the baby but is discovered by Rigsby, who initially thinks the baby is Alan's. Ruth has returned and Alan and Philip give her the baby to mind, leading Rigsby to then think that Ruth is his mother, so he is shocked when she says she hardly knows the father and does not know the baby's name. Both Mr. and Mrs. Brent then ...