Very true. Esther's mother is horrible, Miranda's goes to meetings instead of seeing her daughter, Tim's is invisible, Pomona's is an ass (though it is hinted that her father is not), even Patrick's aunts are a dull, bossy nightmare. And the Marlows themselves seem to have no relations that they are fond of, though Cousin Jon was presumably all right.
Re: liked Patrick's father, but she wasn't all that keen on his mother