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* O2: "Denis is my son." This *must be FALSE* because we just established Olga \u2260 Denis.\n * Since O2 is FALSE, O1 *must be TRUE* (Anna's son is NOT Maxim). So, Anna \u2260 Maxim.\n * Current state: Anna \u2260 Denis, Anna \u2260 Maxim, Irina = Kirill, Olga \u2260 Denis.\n\n6. **Time for the big reveal and final deductions!**\n * We know Anna's baby is not Denis and not Maxim. The only baby left is Kirill. But wait, Irina's baby is Kirill! This means there's a problem again. Let's re-trace my steps very carefully!\n\nAh, the beauty of logic puzzles, even the *solver* can get tangled! Let's restart the solution, focusing on avoiding early contradictions by being *super* systematic and using a grid if needed. The core issue might be assuming which clause within a speaker's statement (A1 vs A2) is true or false prematurely, rather than testing the implications for *all* statements given the rule. The key is that *the entire puzzle must be consistent*.\n\nLet's use a systematic grid approach, which is often the best way for these types of puzzles. We'll list Mothers and Babies.\n\n| Mother \ Baby | Denis | Kirill | Maxim |\n|--------------|-------|--------|-------|\n| Anna | | | |\n| Irina | | | |\n| Olga | | | |\n\n**Rule**: Each mother makes one true (T) and one false (F) statement.\n\n**1. Analyze Olga's Statements:**\n* O1: Anna \u2260 Maxim (Anna's son is not Maxim)\n* O2: Olga = Denis (Denis is my son)\n\n * **Case 1.1: Assume O1 is TRUE, O2 is FALSE.**\n * So, Anna \u2260 Maxim. (TRUE)\n * And Olga \u2260 Denis. (FALSE, meaning O2 is false). \n * From Olga \u2260 Denis, Olga's baby is either Kirill or Maxim.\n * If Olga \u2260 Denis and Anna \u2260 Maxim, let's see where this leads for the others.\n\n * **Case 1.2: Assume O1 is FALSE, O2 is TRUE.**\n * So, Anna = Maxim. (FALSE, meaning O1 is false)\n * And Olga = Denis. (TRUE)\n * From Anna = Maxim, we fill that in. From Olga = Denis, we fill that in.\n\n | Mother \ Baby | Denis | Kirill | Maxim |\n |--------------|-------|--------|-------|\n | Anna | NO | NO | YES | \n | Irina | NO | NO | NO | (*can't be Maxim, Denis, Kirill yet*)\n | Olga | YES | NO | NO |\n\n * If Anna=Maxim and Olga=Denis, then Irina *must be Kirill* (by elimination). So, Irina = Kirill.\n * Now let's test *all* statements with this provisional solution: **Anna=Maxim, Irina=Kirill, Olga=Denis**.\n\n * **Anna's Statements:**\n * A1: "My baby's name is Denis." (Anna=Denis). This is FALSE (Anna=Maxim).\n * A2: "Kirill is Irina's son." (Irina=Kirill). This is TRUE.\n * *Result for Anna*: One F, one T. This works!\n\n * **Irina's Statements:**\n * I1: "My baby is Maxim." (Irina=Maxim). This is FALSE (Irina=Kirill).\n * I2: "Olga's son is not Denis." (Olga \u2260 Denis). This is FALSE (Olga=Denis).\n * *Result for Irina*: Both statements are FALSE. **This contradicts our rule!** Therefore, Case 1.2 (Olga=Denis) is incorrect.\n\nThis means we *must* go back to **Case 1.1: O1 is TRUE (Anna \u2260 Maxim), O2 is FALSE (Olga \u2260 Denis)**.\n\n* So, we know: **Anna \u2260 Maxim** and **Olga \u2260 Denis**.\n\nNow let's analyze **Irina's Statements** with this new information:\n* I1: Irina = Maxim\n* I2: Olga \u2260 Denis (This is TRUE based on our deduction from Olga's statements!)\n* Since I2 is TRUE for Irina, then I1 *must be FALSE* (Irina \u2260 Maxim) for her statements to follow the one-true-one-false rule.\n* So, we now know: **Irina \u2260 Maxim**.\n\nLet's update our known facts:\n* Anna \u2260 Maxim\n* Olga \u2260 Denis\n* Irina \u2260 Maxim\n\nLet's summarize this in our table:\n\n| Mother \ Baby | Denis | Kirill | Maxim |\n|--------------|-------|--------|-------|\n| Anna | | | NO | \n| Irina | | | NO |\n| Olga | NO | | |\n\n* Look at the 'Maxim' column: Anna doesn't have Maxim, Irina doesn't have Maxim. Therefore, **Olga's baby MUST be Maxim!**\n\nNow we have a solid piece: **Olga = Maxim**. Let's add that to our table and update others.\n\n| Mother \ Baby | Denis | Kirill | Maxim |\n|--------------|-------|--------|-------|\n| Anna | | YES | NO | (*Olga has Maxim, so Anna can't*)\n| Irina | | NO | NO | (*Olga has Maxim, so Irina can't*)\n| Olga | NO | NO | YES |\n\n* If Olga = Maxim, then Olga cannot be Kirill or Denis. (We already knew Olga \u2260 Denis, which is consistent). \n\nNow let's analyze **Anna's Statements** with our new knowledge (Olga = Maxim, Anna \u2260 Maxim):\n* A1: Anna = Denis\n* A2: Irina = Kirill\n\n * **Case 2.1: Assume A1 is TRUE (Anna = Denis).**\n * Then A2 must be FALSE (Irina \u2260 Kirill).\n * Current state: Anna = Denis, Olga = Maxim, Irina \u2260 Kirill.\n * By elimination, Irina's baby must be Kirill (the only remaining baby) if Anna is Denis and Olga is Maxim. BUT this contradicts Irina \u2260 Kirill! So, A1 cannot be TRUE.\n\n * **Case 2.2: Therefore, A1 must be FALSE (Anna \u2260 Denis).**\n * Then A2 *must be TRUE* (Irina = Kirill).\n * So, we have: **Anna \u2260 Denis**, **Irina = Kirill**, and **Olga = Maxim** (from previous deduction).\n\n**Final Deduction:**\n* If Irina = Kirill and Olga = Maxim, then the only remaining mother (Anna) must have the only remaining baby (Denis).\n* So, **Anna = Denis**.\n\n**The Solution is:**\n* **Anna's baby is Denis.**\n* **Irina's baby is Kirill.**\n* **Olga's baby is Maxim.**\n\nLet's quickly verify this solution against all statements one last time to make sure everything lines up perfectly with the