I think they are Albert Windsor and Leopold Windsor sons of Lord Nicholas Windsor and the grandsons of the Duke of Kent.
1) Duke of Gloucester2) Little girl - unknown Lady Cosima Windsor3) Spectacled boy - unknown Xan Windsor, Lord Culloden4) Man with only face visible - Earl of Ulster?? Agree
5) Duke of Kent in uniform6) Duchess of Kent7) Earl of St.Andrews - white beard8) Lord Frederick Windsor
9) Lady Sophie Windsor - nice to see her back looking chic after the accident :) aka Lady Frederick Windsor
10) Lady Gabriella Windsor - big earrings11) Prince Michael of Kent12) Spectacled young man - unknown13) Princess Michael of Kent14) Short lady - unknown
15) Small boy - Albert or Leopold Windsor?? Leopold I think
16) Little girl - unknown17) Tim Lawrence18) Princess Royal19) Princess Beatrice20) Lady Louise Windsor - face visible partially21) Duke of York22) Princess Eugenie - only the brim of her hat visible behind Andrew23) Camilla's hat visible behind the Queen24) The Queen25) Duchess of Sussex26) Prince Charles27) Duke of Sussex28) Duchess of Cambridge29) Princess Charlotte30) Savannah Philips31) Duke of Cambridge32) Prince George
33) Young lady without hat - unknown Eloise Taylor I think34) Isla Philips35) Young lady with floral hat - unknown Estella Taylor I think
36) Autumn Philips
37) Peter Philips
38) Small boy - Albert or Leopold Windsor?? Albert I think
39) Lady Helen Taylor40) Lady - unknown41) lady in pink striped dress - unknown
42) lady in wide brimmed hat - unkown is this Lady Gabriella Windsor?43) handsome young man - unknown maybe Columbus Taylor?
44) lady with white necklace - unknown45) Man in yellow tie - unknown
46) Lord Nicholas Windsor?? agree