Ranitidine and Omeprazole

My youngest daughter is having problems with her GERD.

She also has asthma but this is ok at the mo!

She has been on Ranitidine all her life with additions of gaviscon and omeprazole as and when needed.

She has been put back on omeprazole today and its been about 3 years since she was on it before and I can't remember when I gave it to her!

Silly, I know but never thought to ask and then on the label it just says take once daily as directed-really helpful eh?!!

So my question is: When is the best time to give it? She has 4.5mls ranitidine morning and night, before breakfast and just before going to bed. Can I give omeprazole at the same time as the ranitidine if so do I give it in the morning?

I will check with GP in the morning but just thought I'd ask as it will bug me all night now!! Many thanks for your help x