Why a bull here?

One day I visited a Gaushala (cow shed) with my 8 year old niece on her repeated requests. On seeing lot of cows under one shed she was excited beyond measure. Then her eyes fixed on a cow which looked dissimilar to others.

" Mamu (uncle) why is this cow so different," she questioned me as she pointed towards the cow.

I took a quick look. It was a bull.

" It is a bull," I answered.

She remained quite for a few moments. Then a few ladies arrived and on seeing my adorable niece they started to pinch her cheeks. Generally she gets irritated by this but that day she remained calm, busy with the bull puzzle in her mischievous head.

Then to everyone's embarrassment she asked, " What is this bull doing in a cow shed? He should be in a bull shed."

I preferred to ignore her question and the others too did the same as they moved on suppressing their giggle.