Although there are many strands to this story, believe it or not it's very simple.
When your partner goes to court, there is one consideration: What are in the best interests of the child?
A good place to start is the `Welfare Checklist' from Section 1(3) of the Children Act 1989
` ...a court shall have regard in particular to -
(a) the ascertainable wishes and feelings of the child concerned (considered in the light of his age and understanding);
(b) his physical, emotional and educational needs;
(c) the likely effect on him of any change in his circumstances;
(d) his age, sex, background and any characteristics of his which the court considers relevant;
(e) any harm which he has suffered or is at risk of suffering;
(f) how capable each of his parents, and any other person in relation to whom the court considers the question to be relevant, is of meeting his needs;
(g) the range of powers available to the court under this Act in the proceedings in question.'
That is it. When dealing with the court, the above should be your bible. Don't be concerned with what the ex if it doesn't have any bearing on the above. If she makes allegations just simply say `I refute all allegations' - not doing so is an acceptance that he agrees with them. If the court wants to investigate any allegations she makes, it will.
Otherwise, let her rant away.
Stay child-focused. Put everything in terms of the child: It's not dad's time with the kids' it's the kids' time with their dad', etc.
Mediation should be attempted (in theory). However in my experience (I work as a McKenzie Friend dealing with cases like this on a daily basis) I wouldn't bother. It delays proceedings and quite honestly, you know what the situation is. The worst that will likely happen if you don't try is a judge saying it should be attempted, or ordering it.
Otherwise it's just delay and the ex extending the status quo of poor or no contact (and believe me, the status quo is one of the strongest considerations in a hearing...the ex's solicitor WILL try to stop contact if there isn't any by saying that by ordering it the childrens' lives with be `disrupted').
If I were to make a prediction about what happens if your partner went to court I would say...
She will say she has welfare concerns' at the first hearing - meaning that there will be no contact/supervised contact until they have been investigated - with a CAFCASS report ordered (with a delay of up to 6 months in part of the country). She will almost certainly refused overnight contact because the child is too young' or that his accommodation is unsuitable.
It'll go to a directions/review hearing and on from there...
As he's on legal aid I would urge him to consider the use of a McKenzie Friend - a legal assistant who helps him run his own case. It isn't as hard as you think and there are some really good ones out there (I work with one who does it full time and amongst other things has Rights of Audience in the High Court in London) - some of them charge, some don't. Some are legally qualified, some aren't.
I would also recommend he joins Families Need Fathers. I'm a member, a McKenzie Friend and am a volunteer (as is my partner...who is a stepmother like you). Members includes dads, but also grandmothers, aunts, cousins, sisters and stepmums - about a third of the members are female. You'll find all sorts of useful information on their website.
They have branches around the country, with support meetings (where you can get free advice of solicitors, social workers, McKenzie Friends), a telephone helpline, a forum with people who can help and a lot more.
If you need any advice, get in touch. There is a lot you can do!