No, she wanted to show me something instead

"Yes I remember dear, we did say we'd visit the wreck today," Mom said,
"..but I've got something way more exciting to show you. Follow me!"

Mom rose to her feet and skipped away across the sand - at an unusually brisk pace for her.

"Wait up!" I yelled after her, struggling to run with my oversized sausage bouncing against my leg.

Reaching a part of the beach I had never seen before, I watched Mom run into a small cave and disappear from view. Cursing under my breath, I increased my pace. When I reached the mouth of the cave and peered inside, Mom was nowhere to be seen. On the sandstone walls there were scrawled carvings of mysterious symbols. In the center of the floor there was a rocky outcrop that looked somewhat like an altar.

"Mom?" I called out into the empty space.

I stepped towards the altar and felt a strange energy thrumming within the walls. The magnetic feeling seeped into my consciousness, heightening my awareness. As I drew closer to the altar, my vision cleared. Details became more sharp and colors were more vibrant. I noticed a recession in the makeshift altar, as if something should be placed there. I moved closer to investigate. Suddenly, pinpricks tingled up my shins, thighs and groin, dancing with a mystical energy. Fearing some kind of harmful radiation, I spun around to leave the cave.

"Awesome isn't it honey?" Mom said, having appeared at the entrance of the cave.

"AAH!-"
My heart nearly leapt out of my mouth. Mom stood, hand on hip, holding a large gem in her other hand.

"I don't know what that strange electric feeling is, but I think it's coming from this!"

She held out the gem for me to see.

"And you decided to pick it up?" I scolded her.

I examined the gem closely. It was mostly transparent, with thin veins of white-blue minerals scattered within. It shimmered beautifully in the dim cave light. I could feel the magnetic sensation emanating strongly from it, as if it were surrounded by an invisible fire.

"Wanna see what it can do?" Mom asked with a sinister glint in her eye.

"Um, ok? What does it do?" I asked as Mom closed her eyes and placed the rock on my chest.

I froze solid as electrical sparks exploded through every nerve ending in my body. The sensation rapidly faded and was replaced with a dull heat of my muscles aching, as if I was recovering from a heavy workout. I stepped back, away from the stone, but the sensations were not quelled in the slightest.

I looked down at my forearms. To my shock, they thickened and widened before my eyes, becoming the arms of a jacked bodybuilder. My clothes suddenly felt 2 sizes too small, and I realized that my entire body must be following suit. My chest and shoulders billowed larger, bursting open a couple of buttons on my shirt and exposing hardened pectorals. My quads swelled up, stretching my already strained shorts to the limit. The zipper broke open and the bulging base of my girthy cock strained to escape.

Finally, the aching dissipated and I could regain my ability to think.

"What the f-.. how..?" I spluttered, astonished.

My mom just gawked at me with her mouth open in a lustful grin. Her thighs were squeezed tightly together. One hand flapped the collar of her shirt to fan herself.

"Wanna give it a try darling?" she asked coyly.