The dorsal horn of the spinal cord contains a specialized circuit that relays pain information to higher brain regions like the brainstem and thalamus. This circuit consists of late-born inhibitory and excitatory neurons that form functional pain pathways. Our study aimed to identify brainstem neurons that are born at the same time as spinal nociceptive neurons. We used in utero electroporation to label neurons with GFP at embryonic day 12.5 (E12.5), followed by histological analysis at postnatal day 28. Brain sections were examined using immunohistochemistry and the Allen Brain Atlas to trace labeled neuroprogenitors. We found that these late-born neurons integrate into major sensory pathways, shedding light on how neurons born at the same time contribute to diverse sensory networks.