Rhea was often pregnant but never indeed a mother
Rhea was enraged when Cronus devoured all of her offspring except for Zeus, according to Ovid's Fasti. Even while her youngest child was still alive, she was unable to appreciate being a mother. Even the lions were nursed to satisfy her need for maternity, and the lions later evolved into her spiritual companions. She frequently sobbed because her kids were not home.
Zeus didn't appear to her until he was an adult. They all participated in the Titanomachy battle after being birthed from Cronus' jaws. The war didn't conclude for ten years. When Rhea eventually got to meet her kids, they were all adults with jobs that Zeus had given them. Rhea was thus prevented from having a motherly role.
When she raised the young Dionysus in the tale, her yearning to be a mother was also evident. Zeus had sent Hermes to bring Dionysus to her to appease Hera's wrath. Additionally, according to ancient texts, she was present when Apollo was born. She cleaned Apollo with pure water alongside her sisters Tethys and Theia. They dressed him in a white gown as well. They took care of him while Leto was recovering.