I'd say and this is not legal advice - if you want MORE custody and the father ins't a shmuck as for temporary custody while the child is young to be reviewed later - like when the kid goes to school. I would go in now, judges are oldschool for the most part they wont believe every man can handle a baby without support - but they will believe a man can handle 50-50 parenting of a 4yr old..
Feeling like x is doing it for spite - number one piece of advice NEVER look like you are motivated by emmotions in custody issues...appear cool calm rational at all times. Don't question THEIR motivations just show why you are the best choice. The natural choice and that you support their other parents involvment as much as possible. But that for ease of the child's life its in the CHILDs best interest to have ONE house, with their primary care giver. Like duh
It might be sexist but men have an uphill battle in custody due to stereotypes.
Also dont throw in blanket bad statements about the other parent - touch on them loosely let the other parent explain how their BIPOLAR MEDS impact parenting.....not a long list of strange things they do or how their mother is a wanker....
We argue what we are not firm in our convictions on.
Is the sky blue...yes...but if I say its purple you will just assume I am nuts..
Do not argue what you know to be true
that being with mama while young is better for the child - that will frazzle the other parent and the one that mudslings looses....