I hear that planning summer parties and getting people to come can be difficult. Just a thought but maybe if you could phone the guest's parents and personally invite them rather than sending out another email. And telling them a bit about what the children can expect from the party...if there is a theme etc?
Personally, and this may be just me but I don't like getting email invites. I always wonder how many people have been invited and if our little one will even be missed. I do RSVP but if we do have some conflicts then I don't usually go too far out of my way to make it work if I think alot of people are invited
Also, if you are throwing a party for two different age groups then this may also be part of the problem. I know that my 5 year olds wouldn't be too keen to go to a party where there may be a lot of toddlers as well. After all they are starting to feel grown up and they want a more grown up party to attend...just a thought.
For most of our children we have kept the pre age 5 parties low key...well we do family things and build tradtions but we don't include any one outside of our immediate family. We have made an exception with our DD GRace who had a special little group of friends from preschool and from her music class. We moms were friends and the girls just loved getting together and so attending each others birthdays was a highlight but by in large we didn't do this with our other children. I did a great time throwing these parties though...we had a tea party when she was 4 and when she was 5 we did a fairy themed party which was really a fairy quest...the story started with the invitation...it was so creative and took a ton of work but didn't cost a fortune...just time...we had our older children involved too...our older son played the part of the evil wizard etc.
Ever since those parties when Grace was small, her friends always attend her parties...they still talk about the fairy party and play the fairy cd music that was in their organza grab bags.
If you think there may not be any guests then start planning an alternative party for your son...espcially your older son...put a crown on his head when he awakes on that day and say all his wishes will come true..what is his fav breakfast?...what is his fav thing to wear for the day?...how would he like to spend his time>...I know my little Will just turned 3..which is so much younger than 5...but his favourite birthday things were the homemade shortcake/strawberries I made for his family party and going to the park with his older brothers in the afternoon while I made the cake...we hyped it up and he felt very special that day.
Well those are just a few thoughts...birthdays are a great learning lesson for our children and it teaches them a lot about handling the spotlight etc...being gracious etc.
Enjoy the special milestone as your boys grow a year older. I always thought having a summer birthday would be very nice...oh you could lay on a blanket in the backyard after all the party celebrations were over and stare up into the starry sky...take a moment to talk to your child about how immense the Universe is and how special he is within it.
Happy birthday blessings from Hope