diff --git a/core/skills-endpoints.json b/core/skills-endpoints.json
index d81fcbcc..351db5bd 100644
--- a/core/skills-endpoints.json
+++ b/core/skills-endpoints.json
@@ -1,5 +1,35 @@
 {
   "endpoints": [
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/leon_birthday",
+      "params": []
+    },
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/when_birthday",
+      "params": []
+    },
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/my_birthday",
+      "params": []
+    },
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/color_meaning",
+      "params": []
+    },
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/specific_color_meaning",
+      "params": []
+    },
+    {
+      "method": "GET",
+      "route": "/api/action/leon/birthday/why",
+      "params": []
+    },
     {
       "method": "GET",
       "route": "/api/action/leon/color/favorite_color",
diff --git a/server/src/core/ner.js b/server/src/core/ner.js
index 9f42c704..5fc3339e 100644
--- a/server/src/core/ner.js
+++ b/server/src/core/ner.js
@@ -80,7 +80,10 @@ class Ner {
         const conditionMethod = `add${string.snakeToPascalCase(condition.type)}Condition`
 
         if (condition.type === 'between') {
-          // e.g. list.addBetweenCondition('en', 'list', 'create a', 'list')
+          /**
+           * Conditions: https://github.com/axa-group/nlp.js/blob/master/docs/v3/ner-manager.md#trim-named-entities
+           * e.g. list.addBetweenCondition('en', 'list', 'create a', 'list')
+           */
           this.ner[conditionMethod](lang, entity.name, condition.from, condition.to)
         } else if (condition.type.indexOf('after') !== -1) {
           const rule = {
diff --git a/skills/leon/birthday/README.md b/skills/leon/birthday/README.md
new file mode 100644
index 00000000..e69de29b
diff --git a/skills/leon/birthday/memory/.gitkeep b/skills/leon/birthday/memory/.gitkeep
new file mode 100644
index 00000000..e69de29b
diff --git a/skills/leon/birthday/nlu/en.json b/skills/leon/birthday/nlu/en.json
new file mode 100644
index 00000000..406314d9
--- /dev/null
+++ b/skills/leon/birthday/nlu/en.json
@@ -0,0 +1,66 @@
+{
+  "actions": {
+    "leon_birthday": {
+      "type": "dialog",
+      "utterance_samples": [
+        "What's your birth date?",
+        "How old are you?",
+        "When are you born?",
+        "May I know when is your birthday?"
+      ],
+      "answers": [
+        "I'm born in February 2019.",
+        "My first version has been released in February 2019."
+      ]
+    },
+    "when_birthday": {
+      "type": "logic",
+      "utterance_samples": [
+        "Do you know when is my birthday?",
+        "Do you remember when I am born?",
+        "Do you know my birth date?",
+        "When is Phoebe's birthday?",
+        "Give me my birth date"
+      ],
+      "entities": [
+        {
+          "type": "trim",
+          "name": "person",
+          "conditions": [
+            {
+              "type": "before_last",
+              "to": ["birthday", "birth date"]
+            },
+            {
+              "type": "between",
+              "from": ["when"],
+              "to": ["am","was"]
+            }
+          ]
+        }
+      ],
+      "slots": [
+        {
+          "name": "birth_date",
+          "type": "date"
+        }
+      ],
+      "answers": {
+        "birthday_found": [
+          "%person%'s birthday is the %birth_date%",
+          "%person% is born the %birth_date%"
+        ],
+        "birthday_not_found": [
+          "I'm not sure to remember, would you please tell me what is %person%'s birth date?",
+          "I do not know, please share %person% birth date."
+        ]
+      }
+    },
+    "my_birthday": {
+      "utterance_samples": [
+        "My birthday is the 6th of August",
+        "I am born the @day of @month "
+      ]
+    }
+  }
+}
diff --git a/skills/leon/birthday/skill.json b/skills/leon/birthday/skill.json
new file mode 100644
index 00000000..ff56779a
--- /dev/null
+++ b/skills/leon/birthday/skill.json
@@ -0,0 +1,12 @@
+{
+  "name": "Birthday",
+  "type": "dialog",
+  "bridge": null,
+  "version": "1.0.0",
+  "description": "Leon remembers birthdays and talk about his.",
+  "author": {
+    "name": "Louis Grenard",
+    "email": "louis.grenard@gmail.com",
+    "url": "https://github.com/louistiti"
+  }
+}
diff --git a/skills/leon/birthday/test/.gitkeep b/skills/leon/birthday/test/.gitkeep
new file mode 100644
index 00000000..e69de29b