please help i have 4 parsons finch they all look so similar , all have different size and shaped bib ,they will sit and preen each other and get on very well . would birds of same sex behave like this . or any other tips on behaviour to determine sex . many thanks

Some Australian finches can be positively sexed by the shape of the head, Parsons fall into that category, go to Sexing Star Finches, look up Huckleberries entry of sexing star Finches and apply the same method to sexing Parson Finches, no more guessing, ring your birds according to sex, cocks are rung on the right leg, hens are rung on the left leg, if your birds are youngsters its best to wait for 3 month just to be certain. Good luck