Halsey has a lot of fans supporting their music career, but their baby boy isn't one of them.

The "Without Me" singer, 27, appeared on The Tonight Show Monday and revealed that their 11-month-old son Ender, whom they share with boyfriend Alev Aydin, doesn't like their singing. During the interview, host Jimmy Fallon congratulated Halsey on becoming a mom since they last saw each other and asked if their baby boy loves when they sing lullabies. 

"Oh….no. No, he hates it. He's my biggest critic," the singer responded. "It's funny. My mom, she can't carry a tune in a bucket. It's really bad and when she sings, his eyes light up like she's the stars and the moon. But when I sing, he's not a fan."

Halsey then teased that whenever they sing, Ender gives them a pouty face as if he's going to cry, adding, "And I'm like, ' Alright, most kids would be really happy.'"

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In April, baby Ender made an appearance on his mom's Instagram as the musician shared a series of photos of the two spending time together.

In one snap, Halsey sits outside in the grass while holding Ender's hands as he smiles in front of them. Ender is adorably dressed in green and blue overalls with a matching tie-dye bucket hat.

Another snap shows Halsey standing outside sipping from a coffee mug while holding their baby boy on their hip as he gazes up at them. The singer's Instagram photo dump also included a glimpse at their Easter celebration as baby Ender wears a bunny ears headband. 

"Pockets of happy to get me through 🍎🐰🐛," Halsey captioned the post.

Back in January, Halsey celebrated their son turning six months on Instagram with a collection of sweet photos from the special day. 

The "Bad At Love" singer enjoyed finger-painting with their little one and treated him to a banana oatmeal cake for the occasion. Halsey also crafted a felt crown for the birthday boy, reading "½ Ender." 

In the first photo of their Instagram post, Halsey holds Ender's hand while the 6-month-old sits on a paint-covered surface with a green finger-paint smiley face on his chest. In the second photo, Ender grins while digging his fingers into his cake, and in the third, he lays across from Aydin on the couch while they each sip a drink.

Halsey also shared an up-close photo of Ender's birthday crown, plus an adorable image of their son snuggling with their dog, Jagger. 

"Şişko boy is 6 months. we celebrated with finger paints and a banana oatmeal cake and I made a little crown," Halsey captioned the post. "He sorta just looks like the club kid Pope though... they said it would go by fast but sheeeeeesh." 

Aydin commented on Halsey's tribute, writing, "Jaggy and Endy tho," in reference to the photo of Ender enjoying some cuddle time with Jagger.