BUG ALERT — v1.0.0-beta A bug has been identified in the current release. Issue: When a Kerbal is due to give birth, the vessel she is aboard must be the active vessel (loaded) at the moment of birth. If you are flying a different vessel when the birth timer expires, the newborn will appear in the Astronaut Complex instead of on the ship. Workaround: Before the birth is expected, switch to the vessel with the pregnant Kerbal and stay on it until the birth message appears. This will be fixed in the next release — the newborn will automatically board the correct vessel regardless of which vessel is currently active. Sorry for the inconvenience and thank you for testing!
Grow your own crew. Kerbals are born, age through life stages, and eventually become fully capable adult crew members — all without any external dependencies. Vanilla KSP only.
Pregnancy → Newborn → Child → Teenager → Adult
Each stage takes real in-game time (based on Kerbin days) and comes with its own capabilities and restrictions:
| Stage | EVA | Lab / Harvester | Level|
| Newborn | ✗ | 0% | — | | Child | ✗ | 25% | — | | Teenager (with caretaker) | ✓ | 50% | 0 stars | | Teenager (no caretaker) | ✗ | 20% | 0 stars | | Pregnant – 1st half | ✓ | 100% | full | | Pregnant – 2nd half | ✗ | 40% | level 1 | | Postpartum (10 days) | ✗ | 0% | — |
Non-adults age faster (or slower) depending on ship conditions:
| Condition | Effect |
| Each Cupola Module (max 3) | +5% per cupola | | Vessel landed or splashed | +10% | | Active CommNet to home | +2% | | Scientist as best adult on board | +5% | | Engineer as best adult on board | +3% | | Both biological parents on board | +5% | | No biological parents on board | −5% | | Crew > 75% of capacity | −5% | | Low Support active (career) | −10% |
Newborns and Children require an adult on board or face a death timer:
| Stage | Cost / day |
| Newborn | 150 funds | | Child | 100 funds | | Teenager | 50 funds |
If funds run out → LOW SUPPORT status activates, reducing efficiency and aging speed.
A single toolbar window shows all non-adult and pregnant Kerbals across all vessels:
BreedTheKerbal.cfg — no recompile neededGameData/ folderRaw stats are from the beginning of time until now. Each follower and download entry represents one hour of data. Uneventful hours are omitted.