Is it ok to be flexible with one member of staff with children and not the other?

[Jlb2411]

I have just started work at a small chemist which is just owned and run by one man. He has a counter assistant which has been with him for 6yrs but shy is in her current second maternity leave. I joined and was offered a part time job 6mths ago and was offered 25hrs a week and was offered the hours of 10-3 or 2-7, I opted for 10-3 as I'm a single mum with 3 children but my bass asked if I could do 2-7 until his other lady was back from maternity leave and then we could sort out fair hours between us as we both have children. However she has decided to come back to work in Jan but has stated she is reducing her hours from 25 to 16 and said she is only going to do 3 days a week 10-3. So I'm left with working 5 days 2-7 but my children are really suffering as they come home from school at 3.30 and have no mum til 7pm at night so they are missing a cooked meal, me bathing them, helping with homework etc etc and I'm getting very tired and stressed about it. I feel my boss is being very unfair on me as he said the busiest times of the shop are 3-7 so why is he letter his other member of staff come back from maternity leave and pick and chose he's to suit her which don't suit the business.
When I have tried to talk to him about it he has shut me down and said I took on the job knowing the hours and that even when I suggested a compromise of me finishing early 3nights a week to spend with my children he still said no and also stated that he is also a qualified lawyer and that he knows working law and there is nothing I can do?
I thought women with families should be treated the same or fairly to allow them to work around their children's lives? I have even suggested me reducing my hours to 16 so he could employ a further part time member of staff but he says it will cost him more money.
Do I stand anywhere legally as I don't want to loose my job but I can keep on working 5nights a week til 7 when this other women gets child friendly hours?

[ULA]

Re: Is it ok to be flexible with one member of staff with children and not the other?

Hi Jlb2411 and welcome to the forum.

From what you have said you have worked with your current employer for 6 months. Can I ask when you were offered the part-time job what were the agreed working hours stated in your contract - where they the hours you requested to do or the hours that you agreed to do for the interim until your colleague returned from maternity leave? It would be really useful to know the answer to this question as it would give a possible course of action particularly if they are stated in your contract as the hours you initially requested of 10-3.

You have tried the option of informally discussing this with your boss but this appears not to have been successful but it was the best initial approach to try and I would always advocate this first.

Depending on your answer to my contract question there is another option that can also be considered. Since you have completed 26 weeks employment you have the right to proceed in a more formal way by requesting flexible working yourself. There is a due process for doing this which I am happy to detail but would suggest we look into this further once the answer to the contract question has been resolved.