We are a veggie family (I've hated meat and fish all my life and went veggie aged 8!). I find Rose Elliot fab for recipes to impress my 'suspicious about being veggie' in-laws - Rose's Spaghetti with Lentil and Tomato Sauce (in 'Pasta' or her still-in-print but from the 80's 'The Bean Book') is a winner - especially with added celery and carrot - it's not meaty (else I wouldn't eat it) but very tasty said the in-laws! One of our family faves is what we call the Wrap Meal, tortilla wraps, kidney bean salad or re-fried beans, cheese, hard boiled eggs, salad, cous cous (the flavoured sort), coleslaw, sometimes marinaded tofu or falafel, you could serve this with a meat thing to placate the meat-eaters?
Sorry, reading the initial message you're after meat'n'two veg replacements, Rose certainly has loaves, rissoles, cutlets made from lentils, beans and other pulses. I have a breadcrumbs/nuts/onion mixture which makes great sausages/burger shapes and also base for 'Shepherd's Pie'.
I also know of books specifically written for veggie children - I have one which has Shepherdess pie, veg loaf, some veg pies and casseroles and things made with 'TVP'. It's Good Housekeeping 'Cooking for Vegetarian Children'.
Check out www.parsleysoup.co.uk for some veggie main courses (this site is vegan also but you can add cheese/use butter etc where you wish!)
Hope this helps!