Summer has its own traditions: beach barbecues, South Shore surf and Fourth of July fireworks. For Hawaii island writer Rochelle delaCruz, summer also means visits from mainland keiki.

We love M&M and enjoy them the most in summer. Perhaps you’re thinking chocolate, but in our family, M&M refers to our oldest grandchildren, Micah and Malia.

They began spending summers with us on Hawaii island six years ago when they were 7 and 5, respectively, flying from Ohio to California before embarking on the long stretch across the Pacific. They’re exhausted when they arrive, but you wouldn’t know it from their broad grins.

The pair first visited to see their spunky great-grandmother, who was in her 90s and living alone in Hilo. Nana was still taking daily walks, paying her bills, managing her medications and bragging she had all her teeth. When shopping she would challenge cashiers to "Guess how old I am?!" To her great delight they were always wrong.

We thought it was a good idea for M&M to spend time with her since they were widely separated by age, miles and culture. But the surprise was how well they hit it off.

The woman who had raised my brothers and me was a stern supervisor who demanded polite manners ("Did I hear a tank you?"), erect posture ("Sit UP!"), correct grammar ("If I were you, not if I waz you") and high grades ("What’s dis ‘B’ doin heah?"). Later as adults, when we joked about her unrelenting strictness, she retorted, "An’ das why you all turned out so good!" — taking credit for all our pluses but none of the minuses.

This was the person who sat serenely immersed in a copy of Reader’s Digest or her favorite TV game show while the two M’s chased each other around her house laughing and shouting, slamming doors, kicking slippahs off the lanai.

"Hey, calm down!" I would say, only to have Nana defend their ruckus. "Oh, let them yell all they want," she insisted.

My brain screeched to a halt. Let them yell? Who is this? Where am I? Not only did she allow them to run amok — unheard of in my childhood — but she rewarded them with ice cream from her never-ending stash in the freezer.

It was fortunate that they got to spend several summers together. When Mom gently departed this world three years ago shortly after her 95th birthday, she left M&M with happy memories of warm words and cool Creamsicles.

But Micah and Malia learned more during those and subsequent visits than how to charm their great-grandmother. They started swimming at sandy beaches on the dry side, beginning with Kawaihae where the water is calm, moving on to Beach 69 at Waialea Bay. They now body-surf at Hapuna. They also know how to appreciate Hilo’s rocky shore. We first took them to kid-friendly Onekahakaha, but these days we go to Carlsmith’s at Four Mile, watching as they find the icy brackish spot where spring water hits ocean.

One summer when Micah announced that he wanted to jump off the cliff, his father back in Ohio wondered exactly where we had been taking his precious children. Ka Lae? Laupahoehoe? Kealakekua?

Turns out Micah meant the lava rock tower at Coconut Island where jumping off the structure is a rite of passage for anyone growing up in Hilo. Without hesitation the boy clambered up to the top, stepped back for a running start then sailed off into the bay. His sister, a few years younger, needed a bit more time, but soon she too had conquered the Coconut Island tower.

They also know to order ice shave in Hilo and shave ice elsewhere. We take them for this refreshing treat after a day at the beach, but one time it was too close to dinner when we packed up, so we decided to skip it. The double M’s would have none of it, claiming ice shave after the beach was "tradition" and we were not to mess with tradition. Chastened, we pointed the car in the direction of the shave ice stand. I could swear I heard Nana shout, "Get the rainbow, with ice cream!"

M&M have listened wide-eyed to stories of night marchers in Waipio Valley, of a beautiful woman with her little white dog on the Saddle Road. They know to not get close to honu and monk seals, to watch out for wana and to leave beached jellyfish alone. They eat Spam musubi, bibimbap, manapua, poi and laulau, and sprinkle their talk with "ono," "puka" and "pau." We gave them each an ukulele for their birthday, and they just had their first recital.

We’ve got our eye on another moopuna in Michigan. Kai first came to meet Nana when he was 8 months old and has since made other short visits. He turns 5 next year, and we can’t wait to get our hands on him. It may be a while before he cannonballs off the Coconut Island tower, but there’ll be no holding back on ice shave at Itsu’s. His cousins will see to it.

Rochelle delaCruz was born and raised in Hilo and continues to live on Hawaii island.