youtube chat info - thx to everyone 
English translation only from now on – assisted by Gemini
Nest Life Updates (Other Nest)
11:32 – Two unfamiliar storks arrived at the nest. The chicks reacted differently, showing they can recognise their parents.
11:32 – Two foreign storks entered the nest. One of them grabbed a chick by the down on its head, as if attempting to remove it from the nest. Fortunately, this only lasted for a short moment.
11:43 – The parents are absent.
11:49 – Both intruders are still present at the nest.
11:54 – Both intruders have left the nest.
12:01 – Arrival of a stork.
14:18 – The male arrives at the nest.
14:20 – A stranger arrives. The male protects the chicks.
14:26:06 – Arrival of a foreign stork, likely a female.
14:39 – The male flies away.
15:04 – Female arrives.
15:06 – Feeding of the chicks.
15:09 – The parent flies away.
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The Intrusion (10:36 AM – 11:20 AM)
11:32 AM: Two adult storks arrived at the nest.
Suspicious Behavior: The chatters noticed immediately that the chicks reacted differently, realizing these were not their parents. One chatter (@if576) noted, "I don't know how, but chicks can recognize their parents."
The Attack: It was later explained in Polish that these were two stranger storks. One of them actually entered the nest and grabbed a chick by the fluff/feathers on its head, appearing as though it wanted to eliminate or throw the chick out of the nest. Fortunately, it stopped after a brief moment.
Departure: By 11:54 AM, both intruders had left. Regular viewer @LizNm noted that while strange adults visit nests often, it is highly unusual for intruders to actually step inside the nest like that. She speculated they might be a rival couple from earlier in the spring.

Dad to the Rescue (1:19 PM – 1:49 PM)
14:18 (2:18 PM): The father stork arrived back at the nest.
Another Threat: Just two minutes later (14:20), a stranger returned. Another viewer (@lenka_zet) speculated that this specific intruder might be a female.
Protection: Dad successfully stood his ground and protected the chicks from the intruder before flying away at 14:39.

Relief and Feeding (2:09 PM – 2:11 PM)
15:04 (3:04 PM): A parent returned safely to the nest.
15:06 (3:06 PM): The parent successfully fed the hungry chicks and flew away shortly after, leaving the nest peaceful once again.