Children's story about two families with a bridge between their homes

Question

I am trying to identify several books (I believe it was a series) about the day-to-day lives of two families. I read these books as an elementary school student in the early 2000s.

As I recall, the two families each had three (it may have been two?) children. One family had only sons, and the other family had only daughters. The two families were neighbors on a cul-de-sac, or otherwise lived near each other. The book was set in the second half of the 20th century. I recall there being a swinging footbridge or other trail connecting the backyards of the two houses.

Obligatory Children's Novel With Bridge Disclaimer: I am certain the book is not Bridge to Terabithia

I believe there being several books. I remember one where the three sisters climbed onto the roof of the brothers' house when the brothers were home alone. The sisters then began making shrieks and "oooo's", pretending to be ghosts to scare the brothers. I recall that this scene, of the girls making noises on the roof while the brothers were scared inside, being depicted on the cover of the book.

Answer 1

The Boy/Girl Battle series by Phyllis Reynolds Naylor could be a possibility.

Goodreads.com description of the first book, The Boys Start the War:

Just when the Hatford brothers were expecting three boys to move into the house across the river, where their best friends, the Bensons, used to live, the Malloys arrive instead. Wally and his brothers decide to make Caroline and her sisters so miserable that they'll want to go back to Ohio, but they haven't counted on the ingenuity of the girls.

From dead fish to dead bodies, floating cakes to floating heads, the pranks and tricks continue--first by the boys, then the girls--until someone is taken prisoner! Will the Malloys leave West Virginia? Will the Bensons come back? Trust the four Hatford boys and the three Malloy girls to do anything to get one up on each other in this fun-filled war of the wits.

The copy on archive.org does suggest that there is a bridge.

Wally squinted, studying the car in the driveway of the house at the end of Island Avenue. The large piece of land in the middle of Buckman was not really an island, because water surrounded only three sides of it, but people called it ''The Island" anyway. If you were coming in from the east, you entered Buckman on Island Avenue and kept going until you were out on the very tip, and then you crossed the bridge over into the business district. You might not even have noticed that the river on your right was the same as that on your left; it simply looped about at the end of the island.

....

It was four days later that Beth rushed in with news. She had been reading a book back in the trees near the river when she saw the boys come over the swinging bridge and sneak along the bank on the Malloys' side.