My Sister-In-Law

The other morning I told Annalee that she looked very cute in her princess nightgown.
"Thank you," she said.
"Is it fun to wear a nightgown?" I asked. (She normally wears pajamas.)
"Yeah, Krissy gave this to me," she said.
"Would you like Daddy to buy you a nightgown?" I asked.
"Could you buy me a pink one?" she asked in return. "Krissy bought me this purple one. Could you buy me a pink one?"
"Sure," I said. "I would love to buy you a pink one."
"Do you remember Krissy?" Annalee asked. (Krissy, Annalee's aunt, is my wife's sister.)
"I sure do," I said. "When you marry someone their brothers and sisters become your brothers and sisters, in law. So, Krissy is my sister-in-law. I remember her."
"Oh, she said. "Grampa Read is my sister-in-law."